Insulating Attic Room Under Slate Roof

You may have to build out on the inside a bit to get enough insulation.

Insulating attic room under slate roof.

Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls. Insulating in and around your roof attic space also prevents long term damage from moisture build up or ice damming which results from the warm air trying to escape through the apex of the roof but instead heating up the snow. Normally it would be 50mm but if you have no undertile felt then 25mm would be reasonable. Additionally insulation serves as a way to enhance sound proofing on the uppermost envelop of your house.

Then use spray foam insulation after that finish the ceiling how you would like. Most codes require a specified minimum amount of headroom and it s tough to meet this requirement when insulating a finished attic especially since most. Box out light fixtures. Insulating your roof and attic space will help retain energy in your home often leading to cost savings and comfort improvement.

The gap should be on the cold side of the insulation. I would advise as much insulation between the rafters as you can get in but leaving a 25mm gap and another 40 or 50mm continuous layer beneath the rafters. Water is insulation s enemy. It creates a breeding ground for mold and mildew and ruins the air trapping pockets that block heat flow.

To meet all three goals insulating your finished attic ventilating the roof and maximizing headroom use a combination of dense batt insulation rigid foam sheeting and air chutes.